Restatement of Previously Reported Condensed Consolidated Quarterly Financial Statements - Consolidated Statement of Income (unaudited) - Summary of Restatement (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales	$ 4,131.0	$ 3,804.0	$ 7,912.0	$ 7,290.0
Selling, general and administrative	945.0	876.0	1,851.0	1,751.0
Other charges	6.0	8.0	47.0	33.0
Other income	(24.0)	(69.0)	(48.0)	(93.0)
Income from continuing operations before income taxes	479.0	659.0	900.0	1,105.0
Income tax expense	104.0	157.0	191.0	267.0
Income from continuing operations	375.0	502.0	709.0	838.0
(Loss)/Income from discontinued operations, net of tax	0.0	(1.0)	6.0	5.0
Net income attributable to controlling and noncontrolling interests	375.0	501.0	715.0	843.0
Net income (loss) attributable to noncontrolling interest	(4.0)	(5.0)	(10.0)	(10.0)
Net income (attributable to PPG)	371.0	496.0	705.0	833.0
Income from continuing operations, net of tax	371.0	497.0	699.0	828.0
(Loss)/Income from discontinued operations, net of tax	$ 0.0	$ (1.0)	$ 6.0	$ 5.0
Income from continuing operations, net of tax (in usd per share)	$ 1.51	$ 1.93	$ 2.83	$ 3.22
Income from discontinued operations, net of tax (in usd per share)	0.00	0.00	0.02	0.02
Net income (attributable to PPG) (in usd per share)	1.51	1.93	2.85	3.24
Income from continuing operations, net of tax (in usd per share)	1.51	1.92	2.81	3.19
Income from discontinued operations, net of tax (in usd per share)	0.00	0.00	0.02	0.02
Net income (attributable to PPG) (in usd per share)	$ 1.51	$ 1.92	$ 2.83	$ 3.21
Scenario, Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales	$ 4,134.0		$ 7,919.0
Selling, general and administrative	963.0	$ 872.0	1,892.0	$ 1,754.0
Other charges		12.0		26.0
Other income	26.0		53.0
Income from continuing operations before income taxes	479.0	659.0	$ 900.0	1,105.0
Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other charges	5.0
Income from continuing operations before income taxes	$ (5.7)
Income from continuing operations, net of tax		(7.0)		(4.0)
(Loss)/Income from discontinued operations, net of tax		$ 2.0		$ 2.0
Income from continuing operations, net of tax (in usd per share)		$ (0.03)		$ (0.02)
Income from discontinued operations, net of tax (in usd per share)		$ 0.01		$ 0.01
Audit Committee Investigation Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales		$ 3,804.0		$ 7,290.0
Selling, general and administrative		872.0		1,754.0
Other charges				26.0
Other income		(69.0)		(93.0)
Income from continuing operations before income taxes		659.0		1,105.0
Income tax expense		157.0		267.0
Income from continuing operations		502.0		838.0
(Loss)/Income from discontinued operations, net of tax		(1.0)		5.0
Net income attributable to controlling and noncontrolling interests		501.0		843.0
Net income (loss) attributable to noncontrolling interest		(5.0)		(10.0)
Net income (attributable to PPG)		496.0		833.0
Income from continuing operations, net of tax		497.0		828.0
(Loss)/Income from discontinued operations, net of tax		$ (1.0)		$ 5.0
Income from continuing operations, net of tax (in usd per share)		$ 1.93		$ 3.22
Income from discontinued operations, net of tax (in usd per share)		0.00		0.02
Net income (attributable to PPG) (in usd per share)		1.93		3.24
Income from continuing operations, net of tax (in usd per share)		1.92		3.19
Income from discontinued operations, net of tax (in usd per share)		0.00		0.02
Net income (attributable to PPG) (in usd per share)		1.92		3.21
Common stock, dividends, per share, declared		$ 0.40		$ 0.80
Audit Committee Investigation Adjustment | Scenario, Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales		$ 3,806.0		$ 7,292.0
Selling, general and administrative		865.0		1,753.0
Other charges				26.0
Other income		(72.0)		(96.0)
Income from continuing operations before income taxes		671.0		1,111.0
Income tax expense		162.0		269.0
Income from continuing operations		509.0		842.0
(Loss)/Income from discontinued operations, net of tax		(3.0)		3.0
Net income attributable to controlling and noncontrolling interests		506.0		845.0
Net income (loss) attributable to noncontrolling interest		(5.0)		(10.0)
Net income (attributable to PPG)		501.0		835.0
Income from continuing operations, net of tax		504.0		832.0
(Loss)/Income from discontinued operations, net of tax		$ (3.0)		$ 3.0
Income from continuing operations, net of tax (in usd per share)		$ 1.96		$ 3.23
Income from discontinued operations, net of tax (in usd per share)		(0.01)		0.01
Net income (attributable to PPG) (in usd per share)		1.95		3.24
Income from continuing operations, net of tax (in usd per share)		1.95		3.21
Income from discontinued operations, net of tax (in usd per share)		(0.01)		0.01
Net income (attributable to PPG) (in usd per share)		1.94		3.22
Common stock, dividends, per share, declared		$ 0.40		$ 0.80
Audit Committee Investigation Adjustment | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales		$ (2.0)		$ (2.0)
Selling, general and administrative		7.0		1.0
Other charges				0.0
Other income		3.0		3.0
Income from continuing operations before income taxes		(12.0)		(6.0)
Income tax expense		(5.0)		(2.0)
Income from continuing operations		(7.0)		(4.0)
(Loss)/Income from discontinued operations, net of tax		2.0		2.0
Net income attributable to controlling and noncontrolling interests		(5.0)		(2.0)
Net income (loss) attributable to noncontrolling interest		0.0		0.0
Net income (attributable to PPG)		(5.0)		(2.0)
Income from continuing operations, net of tax		(7.0)		(4.0)
(Loss)/Income from discontinued operations, net of tax		$ 2.0		$ 2.0
Income from continuing operations, net of tax (in usd per share)		$ (0.03)		$ (0.01)
Income from discontinued operations, net of tax (in usd per share)		0.01		0.01
Net income (attributable to PPG) (in usd per share)		(0.02)		0.00
Income from continuing operations, net of tax (in usd per share)		(0.03)		(0.02)
Income from discontinued operations, net of tax (in usd per share)		0.01		0.01
Net income (attributable to PPG) (in usd per share)		(0.02)		(0.01)
Common stock, dividends, per share, declared		$ 0.00		$ 0.00